Innovation in environmentally related technologies contributes to environmental sustainability and green growth. The patenting activity of regions in environmental technology provides a measure of the efforts and pace of innovation. Japan and the United States display the top performing regions in number of patents in new sectors such as environmental technologies, biotechnologies and nanotechnologies. Patenting activity in environmental technologies is more recent than in biotechnologies and has developed at a faster pace in comparison to nanotechnologies, whose level of activity has not increased substantially in the past ten years. Among the top performing regions in environmental patenting are Japanese regions such as Aichi and Tokyo, which have emerged more recently ().